Search results for "Drought"
showing 10 items of 132 documents
PMT: New analytical framework for automated evaluation of geo-environmental modelling approaches
2019
Geospatial computation, data transformation to a relevant statistical software, and step-wise quantitative performance assessment can be cumbersome, especially when considering that the entire modelling procedure is repeatedly interrupted by several input/output steps, and the self-consistency and self-adaptive response to the modelled data and the features therein are lost while handling the data from different kinds of working environments. To date, an automated and a comprehensive validation system, which includes both the cutoff-dependent and –independent evaluation criteria for spatial modelling approaches, has not yet been developed for GIS based methodologies. This study, for the fir…
A new method to simulate the hydrological state of soil under natural conditions
2009
As micro, macro e mesofaunas no solo respondem frequentemente a variacao das condicoes ambientais, o que resulta em alteracoes na abundância e na estrutura da comunidade. Os efeitos das alteracoes nos parâmetros do solo sao normalmente determinados com amostras recolhidas no campo e trazidas ao laboratorio, ou seja, onde as condicoes ambientais naturais podem nao ser aplicaveis. Criamos um metodo (STAFD - tubos de amostra de solo para inundacoes e secas artificiais), que simula o estado hidrologico do solo in situ com nucleos implantados. As amostras de controle foram comparadas com amostras de tratamentos em que foram simuladas inundacoes de 15, 30, 60 e 90 dias e secas de 60, 90 e 120 dia…
Uniform climate sensitivity in tree-ring stable isotopes across species and sites in a mid-latitude temperate forest.
2014
Tree-ring stable isotopes, providing insight into drought-induced eco-physiological mechanisms, are frequently used to reconstruct past changes in growing season temperature and precipitation. Their climatic response is, however, still not fully understood, particularly for data originating from non-extreme, mid-latitude environments with differing ecological conditions. Here, we assess the response of δ(13)C, δ(18)O and tree-ring width (TRW) from a temperate mountain forest in the Austrian pre-Alps to climate and specific drought events. Variations in stem growth and isotopic composition of Norway spruce, common beech and European larch from dry, medium and moist sites are compared with re…
Proteome analysis of leaves of the desiccation-tolerant grass, Sporobolus stapfianus, in response to dehydration.
2011
Drought and its affects on agricultural production is a serious issue facing global efforts to increase food supplies and ensure food security for the growing world population. Understanding how plants respond to dehydration is an important prerequisite for developing strategies for crop improvement in drought tolerance. This has proved to be a difficult task as all of the current research plant models do not tolerate cellular dehydration well and, like all crops, they succumb to the effects of a relatively small water deficit of -4MPa or less. For these reasons many researchers have started to investigate the usefulness of resurrection plants, plants that can survive extremes of dehydratio…
Influence of arbuscular mycorrhizae on biomass production and nitrogen fixation of berseem clover plants subjected to water stress.
2014
Several studies, performed mainly in pots, have shown that arbuscular mycorrhizal symbiosis can mitigate the negative effects of water stress on plant growth. No information is available about the effects of arbuscular mycorrhizal symbiosis on berseem clover growth and nitrogen (N) fixation under conditions of water shortage. A field experiment was conducted in a hilly area of inner Sicily, Italy, to determine whether symbiosis with AM fungi can mitigate the detrimental effects of drought stress (which in the Mediterranean often occurs during the late period of the growing season) on forage yield and symbiotic N2 fixation of berseem clover. Soil was either left under water stress (i.e., rai…
Insurance mechanisms for tropical cyclones and droughts in Pacific Small Island Developing States
2016
One group of locations significantly affected by climate-related losses and damage is the Small Island Developing States (SIDS). One mechanism aiming to reduce such adverse impacts is insurance, with a wide variety of products and models available. Insurance for climate-related hazards affecting Pacific SIDS has not been investigated in detail. This article contributes to filling this gap by exploring how insurance mechanisms might be implemented in the Pacific SIDS for tropical cyclones and droughts. The study examines opportunities and constraints or limitations of some existing insurance mechanisms and programmes as applied to the Pacific SIDS. Eight insurance mechanisms are compared and…
Sex-specific responses to mycorrhiza in a dioecious species.
2011
In most studies about dioecious plants, the role of arbuscular mycorrhizae (AM) and the potential sex-specific differences between the plant hosts have been overlooked. Because plant sexes frequently differ in drought tolerance and AM fungal colonization provides higher resistance to drought, we investigated whether the relation of mycorrhizal fungi with either male or female Antennaria dioica plants differs using a factorial experiment. We hypothesized that because AM usually increase growth rate and male plants usually grow larger than females, males should gain more benefit from the mycorrhizal symbiosis in terms of mineral nutrition and water supply. Because of higher demands of carbohy…
Desalination. From a questioned resource to a necessary and strategic resource during drought situations for the water supply in the Segura River Bas…
2018
En España, la desalinización ha cobrado un gran impulso en las dos últimas décadas gracias a la aprobación en 2001 del Plan Hidrológico Nacional y en 2004 del Programa A.G.U.A. Ello ha sido motivado por dos factores principales: 1) Las recurrentes e intensas sequías en las últimas décadas, en especial, la de los años noventa en la que se puso de manifiesto la necesidad de la búsqueda de nuevas fuentes y la apuesta por los recursos hídricos no convencionales (desalinización y aguas regeneradas depuradas); y 2) Cambio del antiguo paradigma hidráulico basado en el incremento de la oferta mediante las transferencias de aguas. El objetivo de esta investigación es analizar el rol que ha desempeña…
Urban Stormwater Management, A Tool for Adapting to Climate Change: From Risk to Resource
2020
The effects of climate change on rainfall in the Mediterranean region are manifested in an overall decreasing trend, and greater irregularity in annual volumes and the city of Alicante is no exception. In addition, there has also been a spread of the urbanised area, which has led to an increase in the flood risk in urban areas (due to a greater runoff and the occupation of flood hazard areas) and drought events due to an increase in the water demand. In light of these new scenarios, the Mediterranean cities should design adaptation systems based on rainwater harvesting within the framework of a circular economy. This study analyses the integration of rainwater in flood and water demand mana…
Drought-related cholera outbreaks in Africa and the implications for climate change: a narrative review.
2021
ABSTRACT Africa has historically seen several periods of prolonged and extreme droughts across the continent, causing food insecurity, exacerbating social inequity and frequent mortality. A known consequence of droughts and their associated risk factors are infectious disease outbreaks, which are worsened by malnutrition, poor access to water, sanitation and hygiene and population displacement. Cholera is a potential causative agent of such outbreaks. Africa has the highest global cholera burden, several drought-prone regions and high levels of inequity. Despite this, research on cholera and drought in Africa is lacking. Here, we review available research on drought-related cholera outbreak…